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Grown in moist chamber, from Acer saccharum collected from this location on the 25 April 2021.
Small dark synnematous with long conidia

Synnemata, dark, rather undefinite, typical of the genus, but with very smooth stipe. Conidiophore, not observed, but assumed to produce single conidia apically.

Conidia are hyaline, somewhat club shaped, for the most part faintly septate (except for a few conidia deep in the conidiomata), probably up to 9 septa but difficult to be sure. Conidia measure (30)35-45(48)x2.3-3.3 avg 40.2x2.8 (n=50).

This collection seem to fit well with Illman and White (1985) concept for this species, by having synnemata with smooth stipe, club shaped conidia which measure about 40u in length and with faint septa. However, I think all prior collections of this species are from Europe, but it might be overlooked.

Should be compared with M. ulmi which have somewhat longer conidia with more evident septa. However these difference seem somewhat poorly defined, especially considering that one of my collection of M. ulmi with somewhat shorter spores and isolated from a non ulmus host seem genetically identical to my other collection of M. ulmi from ulmus.

A few of these live in the soil of my plant. This one liked to hang around the art studio and walk on the paintings. I found him in my brush water. That’s why he’s all mangled. I was certain he was still alive when I pulled him out, but I don’t think he survived long. I’m not sure they survive too long anyway so I’m trying not to take it too hard.